Ancistrocladus letestui
Ancistrocladus letestui in Bull. Soc. Bot. France 98: 18. 1951 sec. Taylor & al. 20051
- Holotype: Gabon. Estuaire Prov.: region de Lastoursville, region de Monts Iboundji, 27 Dec. 1930, G. M. P. C. Le Testu 8627 (holotype, P; isotypes, BM, BR, EA).
Notes
The large pits on the leaves of Ancistrocladus letestui are usually oblong and larger in size than in other species of Ancistrocladus and apparently are distinctive for this species when they are present. The mature inflorescence bracts also appear to be distinctive for this species: on young inflorescences they have a form similar to the bracts of several other species, ovate with a central abaxial gland, but as the flower buds develop they become elongated below the abaxial gland, which enlarges markedly giving the bracts a spathulate shape with a cucullate apex. These distinctive bracts persist through the fruiting stage (e.g., Halle 2648, P). Also frequently distinctive in A. letestui is the bark of the branchlets, which is often ornamented with small protuberances formed from obtuse cylindrical multicellular extensions of the epidermis; however, these structures are not found on all specimens of this species. A number of specimens of A. letestui also are distinctive in having relatively very narrow leaves, but leaf shape varies markedly within the species and does not alone distinguish A. letestui (e.g., Halle 3955, P, with the full range of leaf forms, the distinctive bracts, and the distinctive branchlet protuberances).
Conservation
With an EO greater than 20,000 km2 and existing in Nigeria, Cameroon, Gabon, and the Republic of the Congo: Least Concern; with far fewer collections available, Cheek (2000: 875) proposed a status of Data Deficient (DD).
Description
Juvenile plants branched saplings to 2 m tall, lacking hooked branchlets; stems usually with small epidermal protuberances near apex. Juvenile leaves numerous, crowded near apex of sapling branches, linear-lanceolate, 29.0-35.5 X 1.4-1.6 cm, L/W 20.7-25.4, at apex caudate-attenuate then narrowly rounded at tip, at base long-attenuate with blade tissue ultimately very narrow, drying papyraceous; pits monomorphic, small, scattered on ab-axial surface, on adaxial surface few and scattered along midrib, margins, and apex; midrib adaxially narrow and very shallowly sulcate, abaxially prominent, on some leaves terminating in a gland ca. 0.2 mm diam.; secondary veins ca. 40 pairs, brochidodromous; secondary and tertiary venation adaxially prominulous and poorly differentiated from each other, abaxially secondary prominulous and tertiary venation plane to slightly sunken; margins plane to thinly revolute. Adult stems climbing to 30 m high, to 5 cm diam., not twining, with bark gray, with shallow longitudinal fissures, bearing some scattered leaves and lateral branchlets to 30 cm long, lateral branchlets each bearing 1 to several hooks and sometimes a terminal cluster of leaves, main stems and lateral branchlets smooth or sometimes with small epidermal protuberances similar to those on saplings; hooks recurved to spiraling, 7-16 mm diam. Adult leaves drying chartaceous, on both surfaces dull or somewhat shiny, in life not seen, drying discolorous, dark brown above, somewhat lighter brown beneath; pits dimorphic, small pits sparse to frequent though scattered on abaxial surface, sparse and concentrated along margins on adaxial surface, large pits (0.5-)2.0-4.0 X 0.5-1.0 mm, oblong or sometimes circular, 1 to 3 on each surface; midrib adaxially narrow and plane to shallowly sulcate, abaxially prominent, sometimes terminating in a tiny gland; secondary veins prominulous on both surfaces; tertiary veins reticulated and prominulous on both surfaces; margins plane to thinly revolute; stem leaves with per-sistence unknown, narrowly oblanceolate to oblanceolate, 4.0-42.9 X 1.1-5.1 cm, L/W 3.0-17.2, at apex acute to rounded, at base truncate to long-attenuate; secondary veins 8 to 33 pairs; leaves at branchlet apices with persistence unknown, narrowly oblanceolate to elliptic-oblanceolate, 7.5-32.4 X 1.0-6.7 cm, L/W 3.5-15.5, at apex rounded or obtuse to attenuate then narrowly rounded or subacute, at base long-attenuate; secondary veins 8 to 23 pairs, with intramarginal vein situated 1-4 mm from margin. Inflorescence lax, paniculate, lateral or subterminal among leaves at apices of branchlets, without hooks, occasionally bearing bracteal leaves similar to adult stem leaves (e.g., Le Testu 8627, P); peduncle 2.2-6.2 cm long, sometimes curved; branched portion corymbiform, 6-13 X 12-23 cm, dichotomously branched; bracts at early anthesis lanceolate to triangular-oblanceolate, 1.0-1.9 X 0.6-0.8 mm, at apex acute to obtuse and fimbriate, at base spathulate to acute, abaxially with a discoid gland occupying 1/2-2/3 of the surface, by late anthesis bracts growing to 3.0-3.5 mm long and becoming cochleate to clavate by expansion of gland and incurving of enlarged apex; pedicels 4-9 mm long. Flowers all pedicellate; sepals 5, oblong, rounded and entire at apex, at base truncate and shortly decurrent on ovary, red-orange, abaxially of-ten with 1 or 2 raised glands, adaxially with a few small pits, subequal, 2.0-3.0 X 1.0-2.1 mm; petals 5, convolute, suborbicular, cream, ca. 2.5 X 2.5 mm; stamens 10 in 2 whorls; filaments stout, the shorter ca. 0.3 mm long, the longer ca. 0.7 mm long; anthers ca. 0.4 mm long; ovary partially in-ferior, 1-3 mm long; styles (2 or) 3, ca. 0.9 mm long, stigmas ca. 0.3 mm long. Fruit turbinate; nut ca. 6 X 7 mm, on sides longitudinally shallowly 5- ridged; persistent sepal limbs spreading, chartaceous, unequal, larger 3 sepals oblanceolate, 34 X 11-12 mm, smaller 2 sepals oblanceolate to spath-ulate, 21 X 8-10 mm; perianth drying brown, char-taceous; seed not seen.